Self-setting tamp for blasting



' (No Model.)

H. B. BENNETT.

SELF SETTING TAMI FOR BLASTING. No. 282,061. Patented-July 31, 1883.

UNITED STATES PATENT OFFICE.

HERBERT E. DENNETT, OF SOMERVILLE, MASSACHUSETTS.

SELF-SETTING TAMP FOR BLASTING.

SPECIFICATION forming part of Letters Patent No. 282,061, dated July 31,1883. Application tiled June 2, 1883. (No model.)

.To all whom it may concern.-

Be it known that I, HERBERT E. BENNETT, a citizen of the United States,residing at Somerville, in the county of Middlesex and State ofMassachusetts, have invented certain new and useful Improvements inSelf-Setting Safety-Tamps; and I do declare the following to be a full,clear, and exact description of the invention, such as will enableothers skilled in the art to which it appertains to make and use thesame, reference being had to the accompanying drawings, and to theletters and figures of reference marked thereon, which form a part ofthis specification.

This invention relates to an improved method of tamping explosives forblasting purposes. The usual manner of confining explosives by tampingclay, powdered rock, brick, or other substances upon the charge to beexploded is not only attended with a liability of the displacement ofthe cap, fuse, or electric wire, but also involves a greater or lessdegree of danger from premature explosion and con sequent loss of life.In the use of nitro-glycerine and its products, for this reason, thereis seldom any attempt to confine the explosive effects of the charge bytamping, it being deemed too hazardous. Usually a quantity of thisexplosive, in the form of a cartridge or otherwise, is placed in thereceptacle provided to receive it, and a quantity of sand, or clay, orwater is placed upon it. As none of these have any resisting-powerbeyond their specific gravity, they are of but little use, be ing tooeasily thrown out by the explosion. In the employment of highly-ex)losive materials for blasting, the danger attending the tamping of suchexplosives will be avoided by using a tamp composed of substances thatwill assume a firm set after being introduced into the cavity above orin proximity to the charge.

To this end my invention consists of a selfsetting tamp composed ofsand, calcined plasterof-paris, and water, which is employed in the formof a thick batter or in a partiallyfluid condition, so as to fill thecavity and become firmly set therein without danger of displacing thecap, fuse, or electric wire, or of inducing a premature discharge of theex plosive.

I In carrying my invention into effect I take about equal parts ofcommon plasterers sand and common calcined plaster-of-paris, and mixwith water to the consistency of a thick batter, and, having previouslyplaced the cartridge or other quantity of explosive in its receptacle,where it is to be exploded, and made all the usual arrangements as tofuse, cap, or wire and battery, 1 pour the batter of sand andplaster-of-paris in upon the charge, thus filling up the cavity. Thisbatter will quickly set or harden, and is then ready for the dischargeof the explosive material confined by it. Vherc a fuse is to be used itshould be of the waterproof sort.

If calcined plaster-of-paris is not at hand, any setting cement orhardening plastic will answer. In the absence of sand, a thin bet ter ofclay may be substituted and combined with a suitable proportion ofcalcined plasterof-paris.

If desired, plaster-of-paris can be used alone when moistened to abatter with water for the purpose, or other setting cement may be used,together with sand, earth, clay, pulverized rock, &c.; but I preferthesubstances and proportions as above stated.

Nitro-glycerine has over ten times the explosive power of gunpowder, andwhen co11 fined by my improved safety-camp its employment will greatlyreduce the cost of blasting, besides obviating the ordinary danger tolife, limb, and property.

My invention is illustrated in the annexed drawing, in which Arepresents a blasting cartridge; B, the electric wires, setting cementfor tamping the charge.

Having thus described my invention,what I claim as new, and desire tosecure by Letters Patent, is

The herein-described method of tamping explosives for blasting purposes,which consists in confining the charge with a self-setting cement,substantially as described.

In testimony whereof I aiiix my signature in presence of two witnesses.

HERBERT ENOS DENNETT.

Witnesses:

EUGENE B. HAG'AR, Guns. L. Fannswonrn.

and C the self-

